One in three adult Danes has had COVID since November: study

Every third adult in Denmark is believed to have had COVID-19 since November when cases began to surge with the emergence of the Omicron variant, health authorities said Thursday.

This is almost double the number of officially registered infections. The country of 5.8 million has recorded over 1.8 million confirmed cases of since the start of the pandemic, a figure that includes both children and adults.

"We estimate that 32 percent of the healthy adult population between 18 and 72 years of age has been infected between November 1 last year and January 28 this year", Christian Erikstrup, a professor at the Aarhus University Hospital, said in a statement published by Denmark's infectious diseases agency SSI.

The SSI study was based on 5,000 blood donor samples and was aimed at determining the real number of people who had contracted the virus.

"The results indicate that the obscured number, that is the proportion of infected who haven't tested positive, are between a third and half of all infections," SSI director Henrik Ullum said.

With more than 60 percent of the population having received a booster dose and the high penetration of Omicron, health authorities estimate that about 80 percent of Danes have immunity to severe forms of COVID-19.

On Tuesday, SSI estimated that the Omicron wave had reached its peak in and around Copenhagen.